Question

Hurro！
我正在尝试编写我的第一个Android应用程序，而且我遇到了一堵砖墙。

我希望允许用户为每日时间表设置“开始”和“停止”时间。我已经成功实现了TimePickerDialog和它旁边的TextView，但我不能为我的LIFE弄清楚如何将用户选择的时间保存到SharedPreferences字符串。

代码如下（为清楚起见而剥离）：

@Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.setup);
        // Retrieve the shared preferences
        mUserSettings = getSharedPreferences(USER_PREFERENCES, MODE_PRIVATE);

        // capture our View elements
        mTimeDisplayStart = (TextView)  findViewById(R.id.TextView_ScheduleStart_Info);
        mPickTimeStart = (Button) findViewById(R.id.Button_ScheduleStart);

        // add a click listener to the button
        mPickTimeStart.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                showDialog(TIME_DIALOG_START);
            }
        });

        // get the current time
        final Calendar c = Calendar.getInstance();
        mHourStart = c.get(Calendar.HOUR_OF_DAY);
        mMinuteStart = c.get(Calendar.MINUTE);

        // display the current date
        updateDisplayStart();
    }

    // updates the time we display in the TextView
    private void updateDisplayStart() {
        mTimeDisplayStart.setText(
                new StringBuilder()
                .append(padStart(mHourStart)).append(":")
                .append(padStart(mMinuteStart)));
    }

    private static String padStart(int c) {
        if (c >= 10)
            return String.valueOf(c);
        else
            return "0" + String.valueOf(c);
    }

    // the callback received when the user "sets" the time in the dialog
    private TimePickerDialog.OnTimeSetListener mTimeSetListenerStart =
        new TimePickerDialog.OnTimeSetListener() {
            public void onTimeSet(TimePicker view, int hourOfDay, int minute) {
                mHourStart = hourOfDay;
                mMinuteStart = minute;
                updateDisplayStart();
            }
        };

    @Override
    protected Dialog onCreateDialog(int id) {
        switch (id) {
        case TIME_DIALOG_START:
            return new TimePickerDialog(this,
                    mTimeSetListenerStart, mHourStart, mMinuteStart, false);
        }
        return null;
    }

我认为应该在更新TextView的同时保存时间......但我不知道如何做到这一点-.-

我现在花了5到6个小时寻找答案，但我实际上找不到答案。我已尝试使用SharedPreferences.Editor，但这不起作用，因为我需要将时间存储为long，而不是String。
我已经走到了尽头，我真的很感激一些帮助!!

Answer 1

以下方法

    // updates the time we display in the TextView
         private void updateDisplayStart() {
            mTimeDisplayStart.setText(
                    new StringBuilder()
                    .append(padStart(mHourStart)).append(":")
                    .append(padStart(mMinuteStart)));
        });

     SharedPreferences settingsActivity = getSharedPreferences("todolist1",
                    Activity.MODE_PRIVATE);
            SharedPreferences.Editor prefEditor = settingsActivity.edit();

            prefEditor.putString("DateToDisplay",new StringBuilder()
                    .append(padStart(mHourStart)).append(":")
                    .append(padStart(mMinuteStart));  // updates the time we display in the TextView



        prefEditor.commit();
}

此后，您需要从共享首选项中检索数据，如下所示

SharedPreferences settingsActivity = getSharedPreferences("todolist1",
                Activity.MODE_PRIVATE);

        if (settingsActivity.contains(DateToDisplay)) {
            String saveddate = settingsActivity
                    .getString(DateToDisplay, "");

Answer 2

你必须这样做

private TimePickerDialog.OnTimeSetListener mTimeSetListenerStart =
        new TimePickerDialog.OnTimeSetListener() {
            public void onTimeSet(TimePicker view, int hourOfDay, int minute) {
                mHourStart = hourOfDay;
                mMinuteStart = minute;
                updateDisplayStart();

                Calendar cal = Calendar.getInstance();
                cal.set(Calendar.HOUR_OF_DAY, hourOfDay);
                cal.set(Calendar.MINUTE, minute);
                mUserSettings.edit().putLong("starttime", cal.getTimeInMillis()).commit();

            }
        };

Answer 3

SharedPreferences支持long。你可以做点什么

SharedPreferences prefs = getSharedPreferences("prefs", Context.MODE_PRIVATE); prefs.edit().putLong("longKey", longValue).commit();

存储值。要检索它，你可以

SharedPreferences prefs = getSharedPreferences("prefs", Context.MODE_PRIVATE); long longValue = prefs.getLong("longKey", 0l);

Answer 4

这一个用于编辑SharedPreference文件的代码： -

private SharedPreferences myPrefs; myPrefs = this.getSharedPreferences（ “文件名”，MODE_WORLD_WRITEABLE）; SharedPreferences.Editor prefsEditor = myPrefs.edit（）; prefsEditor.putString（ “Mobile_no” 。getText_no.getText（）的toString（）修剪（））。 prefsEditor.commit（）;`

获取值SharedPreference文件的这一个代码： -

myPrefs = this.getSharedPreferences（“myPrefs”，MODE_WORLD_READABLE）; String X = myPrefs.getString（“Mobile_no”，“”）;

X ==获取信息

SharedPreferences和TimePickerDialog

4 个答案: